The method according to the preamble is substantially known from U.S. Pat. No. 3,974,699, disclosing a method for measuring, for example, the position of the blade of a road grader in relation to the horizontal level.
In particular, but not solely, the method of the present invention can be used for measuring the height position or the horizontal extension of a bucket or work platform in connection with the beam structure, or a part thereof, of a working machine, such as an excavator, access platform (lifting apparatus) or the like. At present, the height position or the horizontal extension is measured by using angle detecting sensors mounted at points of articulation of the beam structure, and the position of the beam structure is calculated on basis of the information given thereby. A method of this kind has the disadvantage of a particularly difficult mounting of the angle detecting sensors afterwards on working machines with no equipment ready for measuring the height position and/or the horizontal extension. Another disadvantage is the relative complexity of measurement by angle detecting sensors, because the calculation operations required by the same require microprocessor techniques and calculation algorithms due to the fact that the method is based on trigonometric functions.